It would be nice to be able to specify the location of a new field when you are adding it to a layer using the "Add Field" tool. Often it makes sense to have the fields in a certain order. I recognize that you can re-order the fields when you are viewing them in the attribute table, but the order specified there does not persist to the Attributes dialogue when editing or when exporting to send to another user. You used to be able to explicitly state the location you want your new field to be added in the attribute table using the old ArcInfo 'additem' command, but you cannot do this with the ArcDesktop 'Add Field' tool. Often when I am working with a dataset I am having to export it into coverage format in order to add the fields I want before importing it back into the geodatabase so that I can get the fields in the proper order permanently.
This idea has been merged with ArcGIS should allow the ability to permanently reorder fields in a table.